When a plurality of component individual parts are assembled to form a composite component, for example with the aid of a welding method, the individual parts are first fixed relative to one another in the assembly position and then connected to one another. To fix the individual parts, a clamping frame is used, having a plurality of clamping elements, with the aid of which the individual parts are clamped in a defined spatial position. At the same time, the clamping elements, in conjunction with the clamping frame, on the one hand, perform a positioning task, in that they orient exactly in a relative position to one another the individual parts to be connected and, on the other hand, they perform a fixing task, in that they hold the individual parts to be connected in firm contact with one another.
When the component to be assembled in this manner consists of a multiplicity of individual parts, it is often difficult for the clamping elements necessary for fixing these individual parts to be arranged together on the clamping frame such that they are not detrimental to one another and do not overly impair the spatial access of the assembly device, for example, the welding robot. To solve this problem, German Published Patent Application No. 35 36 015 describes, for the application of assembling a body, to arrange the clamping elements and the welding robots at a different height with respect to the clamping frame, for example by the clamping elements being fastened in suspension to the clamping frame, while the welding robots stand on the bottom of the assembly level. Whereas, in the case of the assembly of a vehicle body, this arrangement prevents the clamping elements and the welding robots from being detrimental to one another, it is suitable only for those applications in which there is no direct overlap of the welding robots with the clamping elements. It is therefore suitable mainly for the rapid tacking together of individual parts which are firmly connected to one another in a further process step, this time without clamping elements. Moreover, the method cannot be adopted when the individual parts to be assembled have overlaps and/or undercuts in the assembly regions when they are in the assembled position, so that the access of the assembly device into the assembly regions is obstructed by the clamping elements or by other individual parts.
The assembly of composite components with overlaps and/or undercuts is conventionally carried out in a multi-stage method, using a plurality of clamping frames: first, some of the individual parts are fastened to a first clamping frame by clamping elements and welded. The intermediate part occurring in this case is transferred into a second clamping frame which is equipped with further individual elements held in clamping elements, and there is welded to these further individual elements. Depending on the complexity of the component, a plurality of welding stages and therefore a plurality of clamping frames are required. This is highly cost-intensive, since each clamping frame represents high investment. Furthermore, the multiple reclamping of the intermediate part from clamping frame to clamping frame leads to inaccuracies in the component to be manufactured and is therefore not suitable for composite components to be assembled with high accuracy.
It is an object of the present invention to provide a cost-effective method, with the aid of which a plurality of individual parts, from which a complex composite component is to be assembled, may be positioned and fixed relative to one another during the assembly process, without multiple reclamping being necessary.